Various proposals have been suggested for preloading a mold insert on a lid of multi-part mold apparatus so that the insert will be disposed in a mold cavity wherein foam precursors are poured and reacted to fill the mold cavity and to bond to the insert such that the insert will be formed integrally of a finished composite part.
It is known to manually locate a steel insert on a lid by use of magnets carried on the lid. Such an arrangement requires preloading of the insert on the lid prior to closure and requires that the insert be manually separated from the magnets during off loading of the part.
It is also known to manually press and load a surface plate for a composite structure against a rigid wall of a mold having vacuum ports in the wall to fix the surface plate to the wall during a plastic molding process.
While such apparatus is suitable for its intended purpose it does not provide an arrangement in which an insert can be preloaded into a mold cavity part and then automatically spaced in the mold cavity as a lid part is closed.
Furthermore, such apparatus does not provide for initial piloting of the insert as it is pulled into alignment with the lid as it is closed with respect to a mold cavity part.
One feature of the present invention is to provide a two part pour mold apparatus including means for automatically positioning a preloaded insert against and laterally with respect to a lid following closure of the mold.
Another feature of the present invention is to provide a two part pour mold apparatus having piloting means on the lid which will initially pilot a preloaded insert against and with respect to a lid as the lid is closed and which will retract when the insert is positioned against the lid.
One aspect of the invention is to provide electroformed surfaces with a stud mounting configuration that provides better dependability for repeatable location of an insert with respect to lid and shell cavity parts of a pour mold apparatus; and further, to provide an electroform material also more suitable for use with known mold release coatings such as Teflon.
Still another feature of the present invention is to provide a two part mold apparatus which will reduce the time required to index and position an insert within a mold cavity during automatic pour molding of composite plastic parts.
Still another object of the present invention is to improve pour mold apparatus having a mold cavity part and a lid moveable with respect to a cavity part having a preloaded insert therein and wherein mixhead means are provided to direct foam precursors into the mold cavity to react within a space formed between the shell and insert such improvement comprising: means forming a lid having a cover thereon; piloting means on the lid for aligning the insert in a first relationship with respect thereto; and means forming a plurality of collapsible vacuum cups on the lid; the collapsible vacuum cups being engageable with the piloted insert for positioning the insert in a desired spaced relationship within the mold cavity during fill and reaction of foam precursors.
Still another object of the present invention is to provide apparatus as set-forth in the preceding object wherein means are provided for directing vacuum to the vacuum cups to pick up the insert and hold it with respect to the closed lid thereby to maintain the desired spaced relationship during foam fill; and wherein means are also provided for maintaining vacuum on the vacuum cups following cure of the foam whereby the finished part is lifted and off loaded from the cavity part by the engagement between the insert and the vacuum cups in response to opening movement of the lid with respect to said mold cavity part.
Yet another object of the present invention is to provide an improved method for forming a composite plastic part having a insert therein bonded to reacted foam precursors poured into a mold cavity part comprising the steps of preloading a shell and insert into the mold cavity with the shell conforming to the mold cavity and the insert being loosely disposed in the shell; piloting the loosely disposed insert with respect to a mold lid as it is being closed with respect to the mold cavity and simultaneously attracting the insert against the lid to form a foam cavity into which foam precursors are poured for reaction and bonding to both the shell and the insert.
Still another object of the present invention is to provide a method of the preceding object wherein the piloting is accompanied by evacuation of the space which is formed as the insert is attracted against the mold lid.